In or out?

Chatting with a friend of my wife's whose daughter lives in Spain - and has done for a dozen years or more - brought home to me how much leaving the EU would impact on her and those like her, and indeed on those Europeans living here.  At present an EU citizen can live anywhere in the EU with no need for permission, visas and the like.  But all that would change - my friend's daughter would have to come home, or apply for a visa which would be time-limited and subject to revocation at any time and for any - or no - reason.  Needless to say, both mother and daughter are hoping the Remain side will win the day.